Having been there several times now, I would just suggest a different impression.
First, across the street from WashU is Forest Park, which I seriously think is one of the nicest urban parks in the world. There are just so many different things to do and it is quite attractive.
Then immediately around the other three sides of WashU are nice residential neighborhoods (and where a lot of students live), and then you start getting to some fun local commercial areas. The Delmar Loop is the closest, but there are lots of historic neighborhoods with their own interesting restaurants, shops, and so on. Those are more Uber trips than walking trips, and my S24 is taking a car for his second year to help with those trips, but they are definitely close when you have transportation.
OK, and then there are a couple Metro stops on either end of campus, and those can take you to places like Downtown St Louis, where of course there is a lot to do. Like my S24 just texted pictures from a Cardinals game, he went to a big soccer match (I admit I do not recall why it was big, but we were able to watch on TV and we think we spotted him in the stands), and there are many museums, and so on.
All that said, the campus is beautiful, the South 40 where the first years live is particularly swank, and I think if you WANT to stay in the WashU “bubble”, you can.
But all this other stuff is easily accessible, if you want it. And maybe if you can split some Ubers, it will help.